Today I heard in the Danish Radio (“Danmarks Radio”) that British researcher had improved mathematical performance on subjects by sending electricity through the head. It is presently even on the front webpage of the “P3” channel with the headline “Is it ok to dope the brain?”.

Poor Thomas Z. Ramsøy, that I know, was dragged early out of bed by the radio to comment on the story. He is neuropsychologist, but I don’t think the story is in his line of research.

I got the impression that the research was performed with transcranial magnetic stimulation (TMS), – a technique where you apply a strong magnetic field just outside the head. Performance enhancement through TMS has been carried out before. A few years ago neuroscientist Daniela Balslev and her cos put TMS (or rather repetitive TMS – rTMS – if you are in the know) at the somatosensory hand area in the brain. You know the area “located at 3 cm posterior to the motor hotspot”. With that she was able to enhance the performance in the so-called mirror tracing task. This is a task where you trace lines on a piece of paper or computer screen, but through a mirror (actual or computer programmed). If you turn the computer mouse 180 degrees around you will see how difficult that task is.

Danish Radio doesn’t link to the original article they talked about as far as I can see. They should learn something from British Radio BBC in that aspect. But luckily Google News manages to find a reference. New Scientist writes Electrical brain stimulation improves math skills and references research by Roi Cohen Kadosh. He has done a TMS experiment, – but the mathematical performance fell. Actually the new research is reported to be performance enhancement with so-called transcranial direct current stimulation (TDCS), – a technique where you apply a small current through the brain.

Well at least for the mirror tracing task this is no magic. rTMS decreases the excitability of the somatosensory cortex and hence the processing of proprioceptive input. This reduces the spatial conflict between vision and proprioception, improving performance. As for the mathematical skills, I know nothing :)